Calipers



D. V. ZHUKOFF.

CALIPER.

APPLICATION FILED OCT. 14. 1918.

1,355,724. Patented Oct. 12,1920.

3 SHEETS-SHEET I.

ATTORNEY D. V. ZHUKOFF.

CALIPER.

APPLICATION FILED OCT. 14. I918.

Patented Oct. 12, 1920.

3'SHEE'ISSHEET 2 INVENTOR,

/// muummuuu WITNESSES ATTORN El D. V. ZHUKOFF.

CALIPER.

APPLICATION FILED 001 14. 1918.

Patented Oct. 12, 1920.

a SHEETS-SHEET 3.

I W T x w ATTOR N EY UNITED STATES DMITRY V. ZHUKOFF, OF RICHMOND, VIRGINIA.

CALIPERS.

Specification of Letters Patent.

Application filed October 14. 1918. Serial No. 258,005.

To all whom it may concern:

Be it known that I, DMITRY V. ZHUKorF,

a citizen of Russia, residing at Richmond, in the county of Henrico and State of Virginia, have invented a new and useful Calipers, of which the following is a specification.

This invention has reference to calipers,

and its object is to provide calipers of extreme delicacy. for minute measurements and also adapted for calipering various ob- 'ects. J In accordance with the invention, there is provided a beam with a fixed jaw and a movable jaw. The beam is provided w th a longitudinally disposed screw rod which, however, does not turn and therefore operates after the manner of a ratchet, while the movable jaw carries a yieldable nut in position to grip the screw and operatesafter the manner of a dog, whereby the movable jaw is normally gripped to the screw and may be set at any point therealong with the nut gripping the screw and holding the movable jaw in place. The nut is capable of limited movement in the jaw and means are provided whereby extremely small adjustments of the movable jaw may be made within the range of each coarser movement provided for by the screw rod and yieldable nut.

Furthermore, the movable jaw is provided with automatically operable means of great delicacy whereby extremely minute variations in standardized articles may be detected. The invention also provides for attachments permitting extremely minute measurements of inside and outside diameters, thickness, height and depth.

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming part of this specification, with the understanding, however, that the invention is not confined to any strict conformity with the showing of the drawings but may be changed and modified so long as such changes and modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawings Figure 1 is a side elevation of a caliper embodying the invention.

Fig.2 is a longitudinal section with some parts 1n elevation of the jaw end of the structure and drawn on a larger scale than Fig. 1. I

Fig. 3 is a section Fi 2.

ig. 4 is a section on the line-44 of Fig. 3.

Fig. 5 is a section Fi 4.

ig. 6 is a section on the line 6-6 of Fi 2, with some parts shown in elevation.

1g. 7 is a perspective view of the yieldable nut for holding the movable jaw on the on the line 3-3 of on the line 5-.5 of

beam in different positions of adjustment.

Fig. 8 is a perspective .view of a guide member orwasher associated with the nut of Fig. 7.

Fig. 9 is a perspective view of a wedge member associated with the structures of Figs. 7 and 8.

Fig. 10 is a perspective view of a gib used in the calipers.

Fig. 11 is a spring used in connection with the gib of Fig. 10.

Fig. 12 is an elevation of an end plate forming part of the movable jaw.

Fig. 13 is an elevation of a graduated wedge block or bar.

Fig. 14 is a plan view of a graduated manipulating head for operating the block or bar shown in Fig. 13.

Fig. 15 is an elevation of the jaw end of the calipers for outside measurment of certain structures.

Fig. 16 is an elevation of the right hand jaw attachment shown in Fig. 15.

Fig. 17 is an elevation of additional jaws similar to those shown in Fig. 15 but arranged for inside measurements.

Fig. 18 is a view similar to Fig. 15 but showing means for measuring depths of bores.

Fig. 19 is a longitudinal section of the left hand jaw shown in Fig. 18.

Fig. 20 is an elevation of the right hand face of the jaw shown in Fig. 19 but removed from the fixed caliper jaw.

Fig. 21 is a perspective view of a lever anvil mounted in the movable jaw.

Fig. 22 is a section on the line 2222 of Fig. 6, with the capiler arm of Fig. 16 attached thereto.

Fig. 23 is a section on the line 23-23 of Fig. 22.

Patented Oct. 12.1920.

Referring to the drawings there is shown a beam 1 having at one end a fixed jaw 2, such jaw extending at rght angles to the beam, as is the usual custom, but it may be otherwise related to the beam. The jaw 2 may be actually integral with the beam as indicated, or may be effectively integral therewith so long as the proper relation of the jaw and beam is maintained. The beam 1 is made as long as may be desired for the particular purpose for which the calipers are designed, and in the showing of the drawings, the beam may be considered as somewhat over six inches in length without being restricted to such particular length. As shown in the drawings, the beam 1 is composed of two parallel bars 3, 4 respectively, both projecting from the jaw 2. The bar 3 is spaced from the bar 4 for a short distance and the two bars where facing each other are provided with lon itudinal channels 5 and 6 respectively. t the ends remote from the jaw 2 the two bars 3 and 4 are connected by an end plate 7 so that the parallelism of the two bars may be maint'ained.

Mounted to slide on the beam 1 is a movable jaw 8 which may be similar in shape to the jaw 2. The jaw 8 is provided. with an extension in the form of a casing 9 so sha d as to snugly yet freely fit the bar 1. ne end of the casing is closed by a plate 10, shown separately in Fig. 12, and provided with openings 13, 14 and 15, the opening 15 being intermediate of the openings 13 and 14. The opening 13 is shaped to permit the passage of the bar 3 and the opening 14 is shaped to permit the passage of the bar 4. Fast to the jaw 2 is one end of a screw rod 16 extending lengthwise of the beam between the two bars 3 and 4 and at the end remote from the jaw 2 the screw rod is made fast in the end plate 7 of the beam by a set screw 17, the screw rod 16 passing freely through the opening 15 in the plate 10, said opening 15 being elongated transversely of the plate. The screw rod 16 does not turn about its longitudinal axis.

On one face of the bar 3 there is produced a scale 18 marked from zero .at one end to such a number of units as may correspond to the effective length of the calipers. -The scale is visible through an opening or window 19 in one side of the casing 9 and one long edge of the window is beveled as shown at 20, and provided with an indicating mark 21, thereby facilitating the reading of the scale. The zero mark is so placed that the indicating mark 21 coincides therewith when the working faces of the two-jaws 2 and 8 are in engagement, as is the customary practice with calipers of the type to which this invention relates. The scale 18 and the itch of the threads of the rod 16 coincide. t will be understood that any suitable unit of measure may be chosen for the scale 18 but for convenience it will be considered that the inch scale is the one chosen and, furthermore, the divisions of the scale are fortieths of an inch, whereby smaller divisions of measurement may read by hundredths, thousandths and more minute divisions, with the readings possible up to hundred thousandths of an inch. Of course, if it be desired, the readings may be by the metric s stem.

One side of the casing 9 where engaging the corresponding sides of the bars-3 and 4 is formed with ribs 22, Fig. 5, entering corresponding grooves 23 extending lengthwise of the respective bars. The inner walls of the casing 9 opposite the ribs 22 are formed with recesses 24 in which are lodged gibs 25 Figs. 5 and 6 backed up by springs 26 urging the glilbs constantly toward the bars 3 and 4. ach gib, one of which is shown se arately in Fig. 10, has a longitudinal rib 2 similar to a rib 22 and each bar 3 and 4 has a matching groove 28 similar to a groove 23. The structure is such that the engagement between the casing extension 9 of the jaw 8 is an elastic engagement producing a firm yet yieldable engagement conducive of easy movement of the jaw along the beam 1 with such movement free from lost motion.

Lodged within the casing 9 is a dog shown separately in Fig. 7 and comprising a head 29 from diametrically o posite sides of which extend flexible elastic arms 30 terminating in opposite jaws 31 having teeth 32 of proper p1tch to match and engage the turns of the screw 16, the tendency of the arms 30 being to maintain the teeth 32 in firm engagement with the screw ,16. The jaws 31 have bevel connections 33 with the arms 30 and these connections are beveled on opposite faces, such faces being the inner and outer faces of the connections. The arms 30 project from ears 34 on opposite sides of the head 29, said ears engaging in the grooves 5 and 6 of the bars 3 and 4. Projecting from the head 29 in quadrature with the ears 34 are other ears 35, one of which has on the face remote from the arms 30 a knife edge 36 radial to the head v29, which latter is provided with a central passage 37 through which the screw 16 extends.

Surrounding the screw 16 between the head 29 and the jaws 31 of the dog is a washer 38 provided with diametrically opposite arms or reaches 39, 40 carried thereby 1n parallelism with the longitudinal axis of the washer. Those faces of the reaches 39 and 40 toward each other have longitudinal grooves 41 constituting guides. The opposite side walls of the casing 9 have longitudinal grooves 42, 43 respectively, see Fig. 5, in which the guide arms or reaches 39 and 40 engage and are movable longitudinally of the casing. A spring 44 surrounds the screw 16 between the head 29 and the washer 38 tending to force these two parts away from each other. The reaches 39 and 40 engage the plate 10, wherefore the washer 38 serves as an abutment for the spring 44.

Surrounding the screw 16 between the washer'38 and the jaws 31 is a ring 45 having diametrically opposite wedges 46 engaging the inner bevel faces .of the connections 33. The ring 45 has arms 47 uided in the grooves 41 of the reaches 39 an 40 and projecting therefrom in the same direction as the wedges 46 and extending beyond the jaws 31 through the passage 15 in the plate 10 where the arms terminate in oppositely directed fingers 49 located outside of the plate 10. These fingers are or may be bevel fingers with the bevel faces toward the plate 10 and back of the fingers the outer face of the plate 10 is provided with recesses 50 so that the fingers of the human hand may be readily introduced back of the fingers 49, because of the recesses 50, wherefore, the

. ring 45 with the wedges 46 may be pulled lengthwise of the extension 9, thereby causing the wedges 46 to engage the inner bevels of the connections 33, thus spreading the jaws 31 and moving the teeth 32 out of engagement with the screw 16. The elastlc arms 30 are reinforced. by spring 51 lodged between the arms 30 and the adjacent walls of the bars 3 and 4, the. springs traveling in the grooves 5 and 6 and being maintained between the head 29 and the end plate 10.

In the casing 9 near one end thereof is a chamber 52 extending transversely to the length of the casing. This chamber has a wall 53 toward that part of the casing containing the nut or dog engaging the screw 16, and through the wall 53 there is formed an opening 54 constituting a passage for the knife edge projection or lug 36.

The chamber 52 is shown as of square cross section, although other cross sectional shape will answer, and in the chamber 52 there is lodged an elongated wedge block or bar 55 shown separately in Fig. 13. This bar, which may be of approximately rectangular cross section, has one long side 56 inclined lengthwise, the inclined face engaging the knife edge lug 36 so that on moving the bar 55 lengthwise, the nut or dog, the head 29 of which engaging the screw 16, will have imparted to it a movement lengthwise of the beam corresponding to the inclined or slanting face 56. The length of the slanting surface of the bar and the degree of slant or inclination is such that the full travel of the bar will impart to the screw-engaging dog a travel of one-fortieth of an inch. Associated with the slanting surface is a scale 59 having twenty-five divisions and, since the full effect of the bar causes a movement of one-fortieth of an inch a movement through a single division of the scale 59 represents one-thousandth of an inch of linear movement. Since the dog engaging, the screw 16 is held against individual movement by the-screw, adjustments of the bar 55 are imparted to the jaw 8. Consequently, when the 'aw 8 is made fast to the screw 16 at any. etermined distance from the jaw '2, movements of the bar 55 cause adjustments of the 'aw 8 by amounts not greater than one-fortlethof an inch in extent and in as small measured distances gs one-thousandth of an inch on the scale Alined with the chamber 52 at one end thereof is a hollow projection 60 in which is seated a head 61 havin a screw rod 62 fast and axial thereto. he rod 62 enters through one end 63. of the wedge bar 55, which end is suitably threaded for the purpose. Moreover, the end 63 is split at one side as indicated at 64, and a nut 65 is applied to this split end which is extremely threaded for the purpose so that the grip of the end 63 upon the screw 62 may be .the head 61 has a neck 67 entering the' extension 60 through the overhang. Fast to the neck 67 within the overhang is an exteriorly milled sleeve 68 fast to the neck while between the sleeve and the overhang there is lodged a spring 69 tending to maintain the parts in close frictional relation, taking up all wear and imparting a needed resistance to movement whereby the head 61 will hold positions to which it is adjusted.

The outer end of the extension 60 has a beveled graduated surface 70 and the head 61 has a corresponding graduated bevel surface 71. The graduations or scale on the surface 71 are circular and marked with ten divisions, The scale on the surface 70 is marked with eleven divisions, one of which may have a distinguishing indicia 72 shown in the drawings as an asterisk, but replaceable by any other suitable distinguishing mark. The two scales 70 and 71 serve as a Vernier scale permitting turning movements of the head 61 and consequently of the screw 62 by extremely minute distances, so that the jaw 8 may be conveniently adjusted by distances, as small as one hundred thoustandths of an inch. In order to facilitate the movement of the head 61 by the fingers grasped and the wedges 46 are pulled toward the inner bevel surfaces of the connections 33, thereby spreading the jaws 31 against their natural tendency and the force of the springs 51. In this way the jaws 31 are spread apart and the teeth 32 are moved out of engagement with the threads of the screw 16. This ermits movement of the jaw 8 to any desired extent within the range of the instrument. and on the release of the fingers 49 the springs 51, em gaging the outer bevel faces of the connections 33, together with the normal tendency of the arms 30, more the jaws 31 into engagement with the screw 16 and through the wedges 46 force the latter and the fingers 49 into their normal positions, the fingers 49 being brought into engagement with the outer face of the plate 10.

The spring 44 between the head 29 and the washer 38 holds the knife edge 36 in constant engagement with the inclined edge 58 of the wedge bar 55 and the arms 39 and 40 carried by the washer 48 in engagement with the plate 10, thus holding the several parts tightly in place in a manner preventing any lost motion of the parts involved.

The jaw 2 has the end remote from the bar 1 reduced in thickness toward its worl ing face, which latter is shown at 74, the reduction in thickness forming a toe 75. That end of the jaw 8 remote from the beam 1 is similarly reduced toward the working face of the jaw indicated at 76, thereby constituting a toe 77 The working faces of the two jaws may be plane throughout and these toe portions are also reduced in width whereby the outer faces of the toe portions are adapted to engage surfaces for inside measurement, the working faces 74 and 76 of the toes serving for outside measurement.

The toe end of the jaw 8 is made hollow, formin a chamber 78 and this chamber extends a ong one side of the jaw 8 to near that portion of the jaw adjacent to the bar 3 of the beam 1. Within the chamber 78 there is secured a yoke 79, best shown in Figs. 22 and 23. The yoke 79 carries pivot screws 80 and 81, the latter extending through one side wall of the chamber 78 and provided with a head 82 for the utilization of the screw 81 as a holding screw for the yoke 79. Mounted in the yoke 79 is a block 83 to which is secured a pointer hand 84 of a length to extend to that end of the chamber 78 remote from the toe 77 with its free extremity in indicating relation to a scale 85 visible through an opening 86 in the adjacent wall of the casing 9. A spring 87 fast to the pointer 84 and bearing against an adjacent wall of the chamber 78 serves to urge the pointer toward one limit of its movement. The yoke 79 is provided with an opening 88 through which there is free to slide one end of a pin 89 having a pointed end engagin a set screw 90 carried by the block 83. '.lhc screw 90 is so positioned as to be eccentric to the axis of rocking of the block 83, wherefore, the pointed end of the pin 89 engaging the screw 90 tends to rock the block 79 and with it the pointer 84 in a direction opposite to the action of the spring 87, which direction will carry the imlicating end of the pointer across the scale 85.

The pin 89 is intermedia-tely threaded through a portion of its length as shown at 91. and this threaded portion carries two nuts 92, 93 respectively, between which nuts the threaded portion 91 is surrounded by a coiled spring 94. That end of the pin 89 remote from the pointed end projects through a passage 95 in the working face 76 of the jaw 8 so as to be engaged by an object placed against said working face where the pin projects therethrough.

Mounted in the toe 77 at a point nearer the extremity thereof than the pin 89 is a lever 96 carried by pointed screws 97 suported by appropriate walls of the toe 77. he lever 96 is an angle lever having one arm 98 constituting an anvil projecting through an opening 98 in that wall of the .toe 77 remote from the working face 76.

The lever 96 has another arm 99 on the side of the pivot screws 97 remote from the anvil 98 and this arm 99 has a fork extremity 100 in embracing relation to the pin 89, the fork 100 being provided with knife edge lugs 101 bearing against the nut 98, while the spring 94 engages the other face of the fork 100.

If pressure be brought to bear upon the end of the pin 89 remote from the pointed end the pointer 84 is moved across the scale 85. As the pointer 84 is of considerable length and the leverage is very large, a visible movement of the free end of the pointer 84 represents an extremely small movement of the pin 89. For some purposes such minute movement may be for indicating rather than measuring purposes. Considering the caliper jaw 8 as having been properly set, a movement of the indicator 84 would simply mean that the object being tested merely varied from the exact size from which the caliper had been set, such variation being extremely small. Again the hand or pointer 84 could be utilized as an extremely delicate means for determining the correct set of the calipers with the assurance that if the minimum limit be'one hundred thousandths of an inch by the scales a discrepancy or error from such setting would appear by a movement of the indicator or hand 84 over the scale 85.

The anvil 98 provides means whereby other measuring devices besides the working faces 74 and 76 may be utilized. It is sometimes desirable to use outwardly bowed legs for the outside califpering, or straight or inwardly bowed legs" or inside calipering;

In Fig. 15 two outwardly bowed legs 102 and 103 are shown. The leg 103 terminates at the butt end in ahead 104 with side wings 105 arranged to engage in grooves 106 on opposite sides of the toe 77 and a set screw 107 bearing against an appropriate part of the 'aw 8 serves to clamp the leg 103 in place.

ivoted between ears 108 at the outer end of the leg 103 is alever 109 having a projecting end 110 coacting with the corresponding end of the other leg 102 for contacting with the article to be calipered. The lever v109 is housed in the leg 103 which is suitably shaped for the purpose and at the end remote from the end 110 carries a set screw 111 for engaging the anvil 98, the set screw permitting suitable adjustments. The caliper leg 102 terminates at the butt end in a head 112 and carries a clamp screw 113 similar to the head 104 and screw 107 of the leg 103. When the caliper legs 102 and 103 are applied and the parts are properly adjusted the most delicate engagement of the contacting points of the caliper legs with the object to be measured is indicated by the pointer 84 because of the length of the lever 109, whereby extremely small movements of its end 110 are transmitted to the lever 96 and again to the pointer 84 to greatly multiplied extents.

In Fig. 17 there are shown caliper legs 114, 115. The leg 114 has an outside pointed lug 116 at its free end while'the leg 115 carries lever 109 similar to the lever 109 ofthe caliper leg 103, and the lever 109 terminates in a contact point 110 similar to the end 110 of the lever 109. At the butt ends both legs 114 and 115 are formed similarly to the legs 102 and 103 and the same reference numerals are used except that they are supplied with the exponents a.

In Figs. 18, 19 and 20 there is shown an arrangement whereby height and depth may be measured. There is provided a block 117 with opposed wings 118 having tongues 119 on their neighboring sides, the wings embracing opposite faces of the jaw 2 with the tongues 119 entering grooves 120 on said faces. The block 117 has a recess 121 to receive the toe end of the jaw 2. In the recess 121 are ribs 122 to enter the grooves 106 in the toe end of the jaw 2/ The block 117 has a passage 123 therethrough in the direction perpendicular to the length of the block. the passage receiving a rod 124 snugly yet freely fitting the passage. For applica tion to thetoe end of the jaw 8 is a bracket 125 carryin a lever 126 pivoted to the bracket an provided with an adjusting screw 127. Aset screw 128 is provlded to hold the bracket to the toe 77 and corre sponds to the set screw 107 otthe caliper leg 103. The bracket 125 and. lever 126 are so proportioned that the free end of the lever 126 is in the path of the corresponding end of the rod 124 when moved through the hole 123 from the side of the block 117 remote from the "aw 8.

The rod 124 is made of a definite length, say six inches plus the thickness of the block 117 where traversed b the rod. When the rod 124. is not in use 1t may be lodged in a {:ole 129 extending through the jaw 2 and When it is desired to measure the depth of a hole, say a hole 130 in a body 131, the block 117 is placed against the surface of the body 131 with the rod 124 entering the hole 130 to the bottom thereof, the other end of the rod extending through the block 117 in a direction toward the jaw 8. The length of the rod 124 from that face of the block 117 remote from the hole 130 is measured by means of the calipers by bringing the free end of the lever 126 into engagement with such end of the rod. The distance between the two jaws is then ascertained from the caliper scales and the depth of the hole is found by subtracting the reading of the calipers from the measured length of the rod, ignoring the thickness of the block 117.

Since in the structure shown in the drawings it is assumed that the caliper scale 18 is six inches, the working length of the rod 124 may be taken as six inches. If it be found that the projecting end of the rod 124 as measured by the calipers is two inches, then the depth of the hole 130 is the diflt'erence between six and two making four inches. The depth of the hole 130 may be ascertained with the same accuracy that other measurements are taken with the calipers.

Assuming that the caliper jaws are in engagement and that it is desired to measure or to caliper an object, the movable jaw is first released from the beam 1 by disconnecting the jaws 31 from the screw rod 16. This is done by the operator grasping the fingers 49 and moving the wedges 46 in a direction to cause them to engage the bevel portions 33 of the jaws 31 to spread the latter and thereby move the teeth 32 out of engagement with the screw rod 16. Now

the operator, by pulling on the fingers 49,

is enabled to move the jaw 8 away from the jaw 2 to such a distance as may be desirable or needed. The jaw is then adjusted approximately to the work, the approximation being determined by the pitch of the threads on the screw 16. This means that the jaws'will be as near to determining the desired dimension of the work as the distance between two adjacent turns of the thread on the screw 16. For some purposes this may be near enough. If a more accurate measurement is desired the head 61 is rotated in a direction to move the wedge 55.

a of the aw 8 for a fractional part of the spacing between the adjacent turns of the thread of the screw 16. Since the wedge is of considerable length and the pitch of its slanting face corresponds to the distance between two adjacent threads of the screw 16, a partial lengthwise movement of the wedge perpendicular to the length of the screw may represent a micrometric movement of the jaw 8, which movement is indicated on the scale 59 while the coarser movement of the jaw 8 is seen on the scale 18. For many purposes the coarse adjustment of the movable jawsupplemented. by the fine adjustment of the micrometric means is sufficient.

The calipers of the invention provide for much finer measurements than are possible with the customary forms of calipers, by

providing one of the jaws with pressure responsive measuring means far more delicate than the sense of touch. This is provided for bythe' pointer 84 movable over i the scale 85 and controlled by the pin 89 engaging the work. The construction is such that the movements of the pointer 84 are greatly magnified with respect to those of the ,pin 89 so that the pointer renders visible movements of the pin too small to be otherwise appreciated.

Provision is made for inside and outside calipering of objects by use of additional legs 102 and 103, or 114' and 115. shown in Figs. 15, 16 and17, so associated with the caliper jaws that the measurements are indicated by the pointer 84, extremely small measurements being rendered visible. the great magnification of the movements being due to the multiple increasing leverage of the parts carried by the leg 103 or 115, and acting upon the pointer 84, which latter moves across the scale 85. The same principle of operation occurs in the structure shown in Fig. 18, except that this structure is designed for gaging depths rather than diameters.

What is claimed is 1. In calipers, a beam provided with a jaw fixed thereto, another jaw slidable along the beam, coacting means on the beam and slidable jaw for automatically locking the slidable jaw positively to the beam in determined positions, a micrometer means mounted on the sidable jaw and engaging a that member of the coacting means located on said jaw. the micrometer means having means for moving it transversely to in turn impart sliding movements to the jaw along the beam, representing fractional parts of the spacing between adjacent determined positions of the jaw on the beam.

2. In calipers, a .beam, a jaw fixed to the 66 beam, another jaw slidable on the beam, coacting means on the beam and slidable jaw for automatically locking the jaw positively to the beam in determined ositionstherealong, a wedge member carrled b the slidable jaw and engaging that mem er of the coacting locking means located on the slidable jaw, and means for moving the wedge member transversely of the direction of movement of the slidable jaw along the micrometer screw engaging e wedge member, said micrometer screw and wedge member being related to the space between the determined positions of locking of the beam, said last-named means ijfipluding a slidable jaw on the beam to adjust the slid; j

able jaw intermediate of the determined po-' sitions in which the jaw may be automatically locked.

3. In calipers, a beam,'a jaw fixed to the beam, another jaw movable lengthwise of the beam, a screw rod carried by and fixed to the beam, a separable nut carried by the movable jaw, a wedge member also carried by the movable jaw and in turn movable transversely of the movement of the movable jaw 'along the beam and positioned to act on the nut to impart movements to the movable jaw, and a micrometer screw engaging the wedge member and adapted to move it transversely of the beam.

4. In calipers, a beam, .fixed and movable jaws on the beam, a screw rod fixed to the beam, and a separable nut carried by the movable jaw and constituting the means for actuating the movable jaw in coarse adjustment, and a fine adjusting means for the movable jaw comprising a wedge member with the pitch of the wedge corresponding to the pitch of the threads of the screw rod, said wedge member being movable in the movable jaw transversely of the direction of movement of the movable jaw, and a micrometer screw carried by the movable jaw and operatively engaging the wedge member and the wedge member engaging the separable nut.

5. In calipers, a slotted beam, a jaw fixed to the beam, another jaw slidable on the beam, a screw rod extending lengthwise in the slot in the beam and provided with threads of a predetermined pitch, another jaw mounted on the beam and slidable lengthwise thereof, a nut carried by the slidable jaw and having means by which it is moved into and out of engagement with the threads of the screw rod, a wedge block carried by the movable jaw and engaging the nut and havin a range of travel in the jaw transversely o the direction of travel of the jaw on the beam, the wedge block having a pitch corresponding to the pitch of the threads of the screw rod, and a micrometer screw carried by the movable jaw and operatively entering the wedge block.

6. In calipers. a slotted beam, a jaw fixed to the beam, another jaw slidable on the beam, a screw rod extending len thwise in the slot in the. beam and provided with threads of a 'predetermined pitch, another jaw mounted on the beam and slidable lengthwise thereof, anut carried by the slidable jaw and having means by which it is moved into and out of engagement with the threads of the screw rod, a wedge block carried by the movable jaw and engaging the nut and having a range of travel in the jaw transversely of the direction of travel of the jaw on the beam, the wedge block having a pitch (orresponding to the pitch of the threads of the screw rod, and a micrometer screw carried by the movable jaw and operatively entering the wedge block, said micrometer screw having a graduated manipulating head and provided with a mounting with graduations adjacent to those of the graduated head and constituting a vernier scale.

7. In calipers, a beam comprising two opposed channel members, a jaw joining the channel members at one end, another jaw embracing the channel members of the beam and slidable therealong, a lock member extending lengthwise of the beam between the channel members and having engaging parts spaced apart by determined distances to constitute units of movement, a movable jaw mounted on the beam in embracing relation to the channel members, a latch member carried by the movable jaw to engage the lock member in the beam at determined positions thereon, and a micrometer device carried by the movable jaw in operative relation to the latch member on said movable jaw and adjustable transversely of themovement of the movable jaw along the beam, with a range of adjustment of the micrometer device corresponding to the predetermined units of adjustment provided by the lock member on the beam.

8. In calipers, a beam, a fixed jaw carried by the beam, another jaw movable along the beam toward and from the fixed jaw, a screw rod carried by the beam, a split nut carried by the movable jaw and having a normal tendency to engage the screw rod, means for spreading the split nut in opposition to its normal tendency, a wedge member carried by the movable jaw and engaging the nut to actuate the movable jaw w1th respect to the screw rod, and a micrometer screw operatively engaging the wedge member.

9. In calipers, a beam, a fixed jaw carried by the beam, another jaw movable along the beam toward and from the fixed jaw, a screw rod carried by the beam, a split nut wedge to travel transversely of the direction of movement of the movable jaw.

10. In calipers, a beam, a fixed jaw on the beam, another jaw on the beam movable lengthwise thereof toward and from the fixed jaw, and provided with a casing through which the beam extends, a fixed locking member for the movable jaw extending lengthwise of the beam and having locking means thereon for holding the movable jaw at determined positions spaced by apredetermined unit of measurement, another locking member on the movable jaw coacting with the first-named locking member and having a normal tendency to move into locking position, means for disconnecting the second-named locking member from the first-named locking member, and micrometer means for adjusting the movable jaw into positions between those determined by the locking member.

11. In calipers, a beam, a jaw fixed thereto, another jaw movable along the beam, a micrometer structure carried by the movable jaw and having a range of movement transversely of the direction of movement of the movable jaw, coacting holding means on the beam and movable jaw for locking the movable jaw in positions determined by the locking means, and devices between the micrometer structure and the locking means for releasing the locking means to permit wide adjustments of the movable jaw.

12. In calipers, a beam provided with a longitudinal scale, a jaw fixed to the beam, another aw movable along the beam toward and fromthe fixed jaw, means for temporarily locking the movable jaw on the beam and limiting such looking to points along the beam spaced by predetermined distances representing units of measurement, and micrometer means for imparting to the movable jaw movements along the beam of a total length less than the distance between two adjacent locking points, said micrometer means including a housing extending transversely of the beam and provided with working parts inclosed in the housing.

13. In calipers, a beam provided with a jaw fixed thereto, another jaw slidable along the beam, and micrometer means mounted on the slidable jaw and comprising a housing extending transversely of the beam and the lines of movement of the jaw along the beam, a' wedge in the housing movable transversely of the line of travel of the jaw, a screw for actuatim thewedge and carried by the housing, and means carried by the movable jaw and coacting with the wedge to actuate the movable to extents corits normal tendency, a guide member for themampulatmg means and also constituting a stop member, a springbetween the head carrying the nut and the guide member, a.

wedge block in the path of the head of the nut and movable transversely to the direc tion of movement of the movable jaw to cause relative movement between the nut and movable jaw, and micrometer adjusting means for the wedge block.

15. In calipers, a beam, fixed and movable jaws carried by the beam, a threaded rod carried by the beam, a divided nut carried by the movable jaw in coactive relation to the threaded rod and having a normal tendency to engage the rod, said nut having a head at one end, manipulatihg means for separating the divided nut in opposition to its normal tendency, a guide member for the manipulating means and also constituting a stop member, a spring between the head carrying the nut and the guide member, a wedge block in the path of the head of the nut and movable transversely to the direction of movement of the movable jaw to cause relative movement between the nut and movable jaw, and micrometer adjusting means for the wedge block, the beam having a scale thereon representing larger units of movement, the wedge block having a scale thereon representing smaller units of movement and the micrometer adjusting means having a scale representing still smaller units of movement.

16. In calipers, a beam, a jaw fixed there to, a jaw movable thereon, a threaded rod carried by the beam and extending through the movable jaw with the threads having a predetermined unit of pitch, a divided nut having a normal tendency to enga e the threads of the rod and provided with an engaging portion to one side of the rod, a wedge block carried by the movable jaw to one side of the threaded rod with the wedge in the path of that portion of the divided nut to one side of the rod, said wedge block bein movable in a pathperpendieular to the line of movement of the jaw carr ing it,

and a. screw engaging the wedge b 00k to moveit and having a graduated head, the wedge block and beam each-being graduated with the graduations of the beam, wedge block and head of the screw of diminishing value.

17. In calipers, a beam provided with a jaw fixed thereto, another jaw slidable alon the beam, and micrometer means mounted on the slidable jaw and-comprising a housing extending transversely of the beam and the lines of movement of the jaw along the beam, a wedge in the housing movable transversely of the line of travel of the jaw, a screw for actuating the wedge and carried by' the housing, and means carried by the movable aw and coacting with the wedge to actuate the movable jaw to extents corre sponding to the pitch of the wedge, said last-named means including an elastically mounted member engaged by the wedge for permitting a micrometric movement of the contact portion of the movable jaw.

18. In calipers, a beam, a jaw fixed thereto, another jaw movable therealong toward and form the first-named jaw, means for temporarily locking the movable jaw at .predetermined points along the beam, and

micrometric means for adjusting the movable jaw to extents smaller than those caused by the first-named adjustment and including a wedge and adjusting screw therefor for imparting movements of the jaw along the beam by movements of the wedge transversely of the beam, and spring means between the wedge and the beam for permit ting the micrometric movements of the jaw and holding the wedge in constant engage ment with the jaw.

19. In calipers, a movable jaw having -micrometer means for setting the jaw to desired positions, and a visible indicating means automatically responsive to contact with the work and carried by the jaw with the contact portion on the working face of the jaw, said visible indicating means comprising a pin having one end at the working face of the j aw, and a pivoted indicating hand within the jaw and having its pointer end visible, the pin engaging the contact hand close but eccentric to the pivotal axis of the hand.

20. In calipers, a movable jaw having micrometer means for setting the jaw to de sired positions, and a visible indicating means automatically responsive to contact with the work and carried by the jaw with the contact (portion on the working face of the jaw, sai prising a pin having one end at the working face of the jaw, and a ivoted indicating hand within the jaw and aving its pointer end visible, the pin engaging the contact hand close but'eccentric to the pivotal axis of the hand,said indicating means also including a rock lever engaging and movable visible indicating means com- I by the pin and provided with an anvil accessible at a point spaced from the working face of the jaw.

21. In calipers, a fixed jaw and a movable jaw, means for the micrometric adjustment of the movable jaw, visual indicating means carried by the movable jaw and responsive to pressure at the working portion of the jaw for producing indications, and other caliper jaws having means for the attachment thereof to the first-named caliper jaws with one of said second-named jaws provided with contact means, for the objects to be measured, in position to engage the means by which visual indications are produced by contact.

22. In calipers, fixed and movable jaws, indicating means carried by the movable jaw and responsive to contact with the work to be measured, caliper legs attachable to the caliper jaws, and contact means carried by the caliper leg on the movable jaw for engagement with the visual indicating means carried by said movable jaw.

23. In calipers, fixed and movable jaws,

with the movable jaw having means for the micrometric adjustment thereof, contact responsive means carried by the movable jaw and including visual indicating means, and caliper legs attachable to the cali er jaws with the leg attachable to the mova 1e jaw provided with adjustable work-engaging means for contact with the contact devices belonging to the visual indicating means of the movable jaw.

24. In calipers, fixed and movable jaws, means for the adjustment of the jaws in measuring, a slidable rod, a holder for the slidable rod attachable to the fixed aw, and a contact member attachable to the movable jaw for engaging one end of the rod to determine the amount of projection of the rod from the fixed jaw toward the movable j aw, whereby the rod may be employed for de th or height measurements.

11 testimony that I claim the foregoingas my own I have hereto afiixed'my signature.

DMITRY V. ZHUKOFF. 

